微流道實驗中流體驅動方式多以針筒幫浦為主，其因管路之連接，外接能源等 需求，造成實驗將受場地與背景知識限制。本研究將仿生半透薄膜整合至微流道晶 片，首次使用滲透壓原理產生流體驅動力，以達到不需外接管路與電力的流道驅動 系統，並實驗分析其結果。研究以數種體積莫耳濃度氯化鈉(2M NaCl)溶液作為 滲透驅動液(Draw Solution)，去離子水(Deionized Water)作為供給液(Feed Solution)。以 2 體積莫耳濃度(M)之濃度差為例，可使面積 153.94 mm2 之仿生半透
薄膜水通量到達 22.68 μL/mm2・hr。
本研究探討不同薄膜有效面積、環境溫度、蒸發量、長時間操作與不同驅動液 與供給液間濃度差所產生之流量差異。另外因仿生薄膜無法百分之百阻隔電解質 離子(如Na+ 與Cl-)，故測量供給液端之電導率(ElectricalConductivity)，探討氯化鈉之回滲現象，並進一步探討是否會造成後續生物醫學相關應用影響。本研究亦 開發不同插銷式薄膜夾具，可使用於聚甲基丙烯酸甲酯(PMMA)與聚二甲基矽氧 烷(PDMS)。
於微尺度流動下比較不同濃度驅動液(1 M 與 2 M 之氯化鈉水溶液)流速之 差異，並証實在微尺度流道內應用滲透壓驅動流體的可行性。利用 Y 字型與 Ψ 字 形流道瞭解使用滲透壓作為流體驅動力時，對流道內液體擴散之影響;並進一步展 示硫酸銅溶液與銅離子指示劑平行流入流道中之呈色反應，輔以灰階形式分析，並 與針筒幫浦推動之方法比較。生物研究應用常需抓取稀少細胞，本研究於微流道晶 片出口處使用薄膜夾具插銷作為流體負壓驅動力，流入低濃度巨噬細胞後進一步 紀錄其抓取與定位狀況，並與使用針筒幫浦驅動之相同設計晶片比較抓取率，以探 討此技術於微米級流道應用之發展性。最後將微接觸印刷技術結合半透膜，透過滲 透壓液體驅動力產生之流線操控微粒子排列，探討半透薄膜於微尺度之多元應用。Fluid delivery is demonstrated by pressure difference. According to the principle of osmosis, through the membrane we can generate a osmotic pressure (∆π) by making the feed solution and draw solution concentration different (∆C). We used 2M, 1.63M, 1.26M, 1M, 0.89M, 0.52M, 0.15M sodium chloride solution, 1M magnesium dichloride solution and 1M sucrose solution as the draw solution and deionized water as the feed solution.
The water flux performance of the membrane influences the usability of pumpless device. To understand the performance, we designed three membrane test cells with different active area. In the experiment, each active area is using three different concentration of sodium chloride draw solution and deionized water as feed solution, then timing for an hour to record the volume increment of draw solution. Due to the electrolyte rejection of the membrane is not 100%, we also measured the conductivity of feed solution to verify the usage of biological experiments can be achieved.
We also used different type of PMMA microfluidic to verify the application of osmotic pressure such as Y channel or Ψ channel. There is a plug-in design for the PMMA microfluidic. In microfluidic research, PDMS chip is the most common type of microfluidic. We designed a plug-in to combine the outlet, biomimetic membrane fixture and the draw solution tank. Use the plug-in in cell trap chip to verify the osmotic pressure driven liquid delivery system can replace the pump. Finally, to manipulate cells or particles, we used the technique which is micro contact printing to construct micro structure onto the membrane.